Music and Synth DIY

Eurorack, Schematics, SMD, Synth DIY, Through hole

VCDENV – voltage controlled ADSR (finished)

This is a 6hp Eurorack envelope generator, with attenuated voltage control over attack, decay, sustain and release stages, linear and exponential envelopes, and gated looping and LFO modes as well as standard ADSR.

Main board

Based on Electric Druid’s ENVGEN8 PIC and associated datasheet schematic.

This is a mainly SMD build, with through hole DIP socket for the ENVGEN8 and sone through hole electrolytics, regulators and transistors.

Jacks board

Currently waiting for boards from JLC, and gerbers and KiCad files will be uploaded once it’s built and tested.

#update 1 December 2022

Nearly there. Working with a couple of bodges. New board with minor errors corrected on the way…

# Update 2 January 2023

This version, v1.0, is working now.

I wanted to build a few of these, so I tried getting JLC to part-populate the main board to save time – that worked perfectly and made the builds a lot quicker.

I now have seven of these in my case.

Next, I’m going to make a 2hp expander for the “TIME” parameter and its CV control (had to leave this as a trimmer on the back to keep it to 6hp), plus a +/-5v output for the LFO & gated LFO modes.

If you want to make one or modify it for personal use, the Kicad files and gerbers are here (CC BY-NC-SA 4.0 licence – please be sure to credit Tom Wiltshire @ Electric Druid, the designer of the circuit and the ENVGEN8 PIC it uses, and abide by their licencing terms.)